The FDA this week approved a new drug that is designed to treat infections from the influenza virus.  Here is a newspaper article about the new drug, https://www.nytimes.com/2018/10/24/health/flu-pill-xofluza.html.

The name of the drug is Xofluza and it is designed to cripple the ability of the influenza virus to reproduce and therefore to end your infection.

The release of Xofluza gives us an opportunity to talk about drugs used to treat influenza infections.

First of all, it should be noted that there are no active influenza virus epidemics active in the United States now, and none have been present since the spring.  This is fully consistent with the seasonal nature of typical influenza virus epidemics.  In the US this virus almost always appears in force only after December 1, typically peaks around New Year’s and leaves the country all together by the end of April or so.

Of course, there is the far less common non-seasonal eruption of influenza virus, an explosion of very novel influenza virus appearance called a pandemic, that can happen in any month, but tends to occur only once every many, many years in an unpredictable way.  So when we talk about influenza epidemics, we are really talking about the seasonal variety of epidemic as outlined above.

The Difference between Antibiotics and Anti-flu Drugs

There are a number of anti-flu drugs, the most famous of which is Tamiflu whose generic name is oseltamivir (all anti-viral drugs end with -vir).   They all act to disrupt or interrupt the cycle of viral reproduction.  That works because viruses are essentially tiny packages of genetic code that directs your cells to make more viruses.  Stop the virus from entering your cell or being able to copy itself, and the infection stops.

The word antibiotic refers to a set of chemicals that kill only one type of life, bacteria.  Bacteria are living, complex cells, and so could not be more different from viruses which are not cells, but really tiny packages of information that can copy itself.  Like any cells, bacteria eat and reproduce.  They hurt us by eating our cells.  They tend to cause destruction in one spot, like an ear infection or UTI or strep throat or pneumonia.  Bacteria cause a furious inflammatory response, so if you take an antibiotic and kill the bacteria, the roaring fire they provoke goes out suddenly, and you get dramatically and rapidly better, you are cured!

Not so with viral infections.  Viruses tend to destroy whole sheets of our cells as they rapidly enter zillions of cells lining whatever surface they attack and destroy that lining in a day or so.  A great example is a cold.  A cold is a situation where viruses especially adept at attacking the lining of our nose, throat, and lungs rapidly run through all these cells, leaving the linings quite literally burned off.  A burned lining of the nose leaves it weepy and sore- a runny nose.  A burned lining of the throat hurts- the sore throat.  A burned lining of the lung leaves it very sensitive- cough.

So, if you take an anti-viral, and it kills the virus, but after the virus has burned off your lining, you will not feel better, the drug will not “work” to reduce the suffering.

Xofluza

Xofluza, known generically as baloxivir  (did you notice the suffix -ir?), works by keeping your cell from being forced to use its gene creating machinery to make it copy viral DNA.    This is different than Tamiflu which works by stopping your infected cells from releasing new copies of viruses.

Xofluza is only taken in a one dose course.

Like Tamiflu, it is essentially useless in healthy people with the influenza infections after they have had symptoms for 2 days.

Like Tamiflu, even if taken in the first day or two, it does not give dramatic relief in most cases.

For Xofluza, the average level of relief is one day.  So if the average viral illness makes you sick for 8 days, the person taking Xofluza will be sick for 7 rather than 8 days, which to my mind is not a dramatic difference.

Now, contrast this with the experience of antibiotics treating bacterial infections, say an ear infection.  Don’t take an antibiotic and your ear infection may cause crushing pain for many, many days.  Take an antibiotic, and often your pain is gone, for good, in a matter of some hours, maybe one day.  That is a dramatic relief, it brings the word cure to mind.

Anti-virals do not typically deliver this sort of relief, and if you have a sniffle for more than 2 days, taking them usually offers no relief at all.

For children it is also very important to know that Xofluza is not licensed for use in anyone less than 12 years old.

BOTTOM LINES

1. We need a medication that cures colds and flus, they cause true and deep suffering and agony.
2. We really don’t have such a medication at this time.  There are chemicals that do stop influenza viruses from reproducing, including this new one Xofluza, but the relief they offer is quite limited.  They reduce the number of days of suffering by only a day or so, and if taken after 2 days of symptoms offer no relief at all.
3. This new anti-influenza viral, Xofluza, cannot be used for anyone less than 12 years old.
4. As a new drug, we need to await widespread use to really learn what harms it can cause.  Tamiflu has been seen to cause seizures in some children, we will see if Xofluza has serious side effects.

Overall, Xofluza, like Tamiflu, will not be an important tool in helping children infected with the flu virus.  This drug cannot be used at all for kids under age 12, and like Tamiflu, cannot help those who have had symptoms for even 2 days, and even if used in time only tends to offer very limited relief, not clearly worth the risks it brings.

To your health,
Dr. Arthur Lavin